<?xml version="1.0" encoding="UTF-8"?>
<definitions id="definitions" 
  xmlns="http://www.omg.org/spec/BPMN/20100524/MODEL"
  xmlns:camunda="http://camunda.org/schema/1.0/bpmn"
  targetNamespace="Examples">

  <process id="process" isExecutable="true">

    <startEvent id="theStart" />

    <sequenceFlow id="flow1" sourceRef="theStart" targetRef="callActivity" />

    <callActivity id="callActivity" camunda:caseRef="oneTaskCase">
      <extensionElements>
        <camunda:out sourceExpression="Prefix${aVariable}" target="aVariable" />
        <camunda:out sourceExpression="Prefix${anotherVariable + 1}" target="anotherVariable" />
      </extensionElements>
    </callActivity>

    <sequenceFlow id="flow2" sourceRef="callActivity" targetRef="userTask" />

    <userTask id="userTask" />

    <sequenceFlow id="flow3" sourceRef="userTask" targetRef="theEnd" />

    <endEvent id="theEnd" />

  </process>

</definitions>